Toxicological Assessment of Trace Element Exposure in Relation to Sudden Unexplained Death (SUD): Environmental Geochemistry and Dietary Risk in Central-Eastern Yunnan, China

Sudden Unexplained Death (SUD) has been reported in specific regions of Yunnan Province, China, yet its environmental causes remain unclear. This study aimed to explore the potential toxicological link between trace element exposure and SUD by investigating the concentrations of multiple elements in soil, corn, and drinking water from typical SUD and non-SUD villages in central-eastern Yunnan. Elemental abundances were determined, and dietary exposure and non-carcinogenic health risks for adults and children were assessed. Results showed that soils in SUD villages were markedly deficient in Na but enriched in Se and Cr compared with non-SUD villages. Corn and drinking water were generally low in essential trace elements, with notable Co deficiency in corn and Fe, Li, Mn, and Cu deficiency in water. Cr and Mn in corn were identified as the main contributors to non-carcinogenic risks, especially for children. Comparative analysis with Keshan Disease (KD) villages in Shaanxi Province indicated distinct elemental patterns, suggesting different pathogenic mechanisms. Overall, environmental Na deficiency and exposure to Cr and Mn may be potential toxicological factors associated with SUD, warranting further investigation into their physiological effects and regional disease etiology.